A new pinched-off cold-FET method to extract parasitic capacitances of MESFETs and HEMTs

The extrinsic gate and drain capacitances, C/sub pg/ and C/sub pd/, are extracted based on a physically meaningful depletion-layer model and a linear regression technique. The extraction method can be applied to obtain the small-signal equivalent circuit parameters for the MESFETs and HEMTs. The simulated S parameters based on the new analytical method exhibit great agreement with the measured S parameters from 0.5 to 20 GHz.